7272221 has 6 divisors (see below), whose sum is σ = 7993566. Its totient is φ = 6611000.

The previous prime is 7272217. The next prime is 7272227. The reversal of 7272221 is 1222727.

It can be written as a sum of positive squares in only one way, i.e., 6180196 + 1092025 = 2486^2 + 1045^2 .

It is not a de Polignac number, because 7272221 - 2² = 7272217 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7272227) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 29930 + ... + 30171.

It is an arithmetic number, because the mean of its divisors is an integer number (1332261).

Almost surely, 2^7272221 is an apocalyptic number.

It is an amenable number.

7272221 is a deficient number, since it is larger than the sum of its proper divisors (721345).

7272221 is a wasteful number, since it uses less digits than its factorization.

7272221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 60123 (or 60112 counting only the distinct ones).

The product of its digits is 784, while the sum is 23.

The square root of 7272221 is about 2696.7055827435. The cubic root of 7272221 is about 193.7413654147.

Adding to 7272221 its reverse (1222727), we get a palindrome (8494948).

The spelling of 7272221 in words is "seven million, two hundred seventy-two thousand, two hundred twenty-one".